Method of agglomerating magnetic ore.



PATENTED JAN. 24, 1905.

E. GATES. METHGD OF AGGLOMERATING MAGNETIC ORE.l

APPLUATIGN FILED JAN. 14, 1901. RENEWED NOV. 5, 1902.

UNITED STATES Patented January 24, 1905.

PATENT CEEICE.

ELMER GATES, CF CHEVY CHASE, MARYLAND. ASSIGNCR TC THECDCBE J. MAYER, OFIVASHINGTON, DISTRICT CF COLUMBIA.

IVIETHOD OF AGGLOMERATING MAGNETIC OREH SPECIFICATION forming part ofLetters Patent No. 780,716, dated. January 24, 1905.

Application iiled January 14, 1901. Renewed November 5, 1902. Serial No.130,154.

To n/Z, whom, t may con/cern:

Be it known that I, ELMER GATES, a citizen of the United States.residing at Chevy Chase, county of Montgomery, State of Maryland,

have invented certain new and useful Improvements in Methods ofAgglomerating Magnetic Ore; and I do hereby declare the following to bea full, clear, and eXact description of the invention, such as willenable others skilled in 1o the art to which it appertains to make anduse the same.

My invention relates to the treatment of magnetic iron ore (commonlytermed magnetic sand) for the purpose of causing' the .incipient fusionand union of the particles into lumps or nugget-like particles of largersize adapted for more advantageous use in the final-reduction furnace.To this end I es tablish an electric arc between the ends of zo twooppositely-located feed-troughs or guiding-surfaces, and into said arc Ifeed the magnetic sand from opposite directions, whereupon the electricarc will pass from one body of the falling sand to the other and e'ectthe 2 5 fusion of the particles into small lumps of a size varying fromthat of a wheat-grain to that of an ordinary bean. By reason of the factthat during the operation the arcing takes place between the two streamsof falling sand a corresponding economy in current employed is obtained.Moreover, I feed the magnetic sand with such rapidity that all of it isnot lumped. This is a feature of economy, for the 'reason that enoughsand is always passing to fully utilize the current, none of the currentbeing allowed to pass without doing its maximum amount of lumping.Furthermore, I allow the fused material to accumulate immediately belowthe point of 40 fusion before passing into the hopper, so that the fusedparticles following are allowed to drop onto those previously fused andpartially cooled, but still hot, whereby the fused lumps will adhere toand agglomerate an additional amount of the unfused magnetite and formlumps of increased size. This is a further feature of economy in thepractice of the process.

In the accompanying drawings, Figure l represents in side elevation anapparatus by it.

adapted for the practice of my invention. Fig. 2 represents aperspective view of one of the feed or guide troughs. Fig. 3 representsa perspective view of a modification thereof.

Similar letters of reference indicate similar parts through the severalviews.

Referring to the drawings, A A indicate hoppers for supplying themagnetic sand to inclined feed-troughsas, for instance, the flat platesB, Figs. 1 and 2, having' the side 60 pieces a or the hollow conduit C,Fig. 3. In either event the feed-trough is mounted upon a standard L ofconducting material, prefer ably carbon, and is itself of conductingniaterial, so that when two opposite troughs, as in Fig. l, are locatedopposite each other and are then brought togetherand included in anelectric circuit the subsequent separation of the meeting ends of thetrough will cause an electric arc to span the interval between them. Asindicated in said figure, the opposite terminals of the electric circuitmay be conveniently connected to the standards 7), and the standards aremovable toward and from each other upon the supports D.

Beneath the discharge ends of the troughs is located a tray t, intowhich the streams of fused particles fall and are temporarilyaccumulated. From this tray the particles drop into a hopper E,discharging into a rotatory S0 screen F, and below the rotatory screen Fare located the hoppers Gr and H.

The operation of the invention is as follows: The opposing ends of theinclined troughs B are brought together, so as to establish continuityof the electric circuit in which they are included. The troughs are thendrawn apart, thereby causing an electric arc to span the intervalbetween said ends, whereupon the magnetic sand is fed to the troughsfrom the hoppers A A and descends the inclines. In passing the ends ofthe troughs the falling streams approach each other, and the electricarc, seeking the path of least resistance, passes between the fallingstreams, thereby decreasing in length by reason of the decreasedresistance offered by the shorter interval spanned Care is taken to feedthe magnetic sand at a speed in eXcess of that necessary for theutilization of all of the energ'y of the current, and as a consequencethe current is fully utilized, since it always finds in its pathmaterial upon which to act. The effect of the passage of the current isto fuse or agglomerate the magnetic sand into the condition of smalllumps Varying in size from a wheatgrain to the size of a bean. Thepassage of these lumps into the hopper is momentarily checked orretarded by their accumulation in the tray z5, where they are partiallycooled, but from which they overflow and drop while still hot into thehopper. Thus the fused particles of magnetite are brought into contactJwith the particles previously deposited in the tray and which havepassed the state of fusion, the result being that the fused particlesadhere to and agglomerate with the previously-fused but nowpartially-cooled particles in the tray and form lumps of magnetite ofincreased size. These lumps, together with the attendant excess ofunfused sand, are received in the rotatory screen F, and in passingthrough the screen the fused lumps are received in the hopper H, and thesand is received in the hopper Gr, from which it may be again passedthrough the hoppers A A'.

Having thus described my invention, what I claim is 1. The method ofagglomerating magnetic sand, which consists in establishing an electricarc between opposing' surfaces, feeding opposing' streams of sand oversaid surfaces, and causing said streams of sand to fall freely from saidsurfaces so as to break the arc originally formed and establish arcingfrom one of the falling streams to the other, thereby fusing andagglomerating the sand into small lumps of a size varyingsubstantiallyfrom that of a wheat-grain to that of a bean.

2. The method of agglomerating magnetic sand, which consists inestablishing an electric are between opposing surfaces, and feedingopposing' streams of sand over said surfaces at a rate in excess of thefusing capacity of the arc, and so that the arc shall pass from onestream to the other, and, in its passage, shall fuse and agglomerate thesand into small lumps of a size varying substantially from that of awheat-grain to that of a bean, with the maximum utility of the fusingcapacity of the current; substantially as described.

3. The method of agglomerating magnetic sand, which consists inestablishing an electric arc between opposing' surfaces, and feedingopposing streams of sand over said surfaces, so that the arc shall passfrom one stream to the other and fuse and agglomerate the sand intosmall lumps of a size varying substantially from that of a wheat-grainto that of a bean, and delivering said fused particles onto anaccumulation of previously-fused and partially-cooled particles, wherebysaid fused particles agglomerate additional unfused particles and formlumps of increased size.

In testimony whereofl aflix my signature in presence of two witnesses.

ELMER GATES.

fitnessesz l EDWIN S. CLARKsoN, J. A. GoLDsBoRoUGH.

